diff --git a/setup.py b/setup.py
index c0e343e5..0105f80b 100644
--- a/setup.py
+++ b/setup.py
@@ -85,7 +85,7 @@ except ImportError:
 
 # Take a look at http://www.python.org/dev/peps/pep-0386/
 # for a consistent versioning pattern.
-PSYCOPG_VERSION = '2.5.4'
+PSYCOPG_VERSION = '2.5.5.dev0'
 
 version_flags   = ['dt', 'dec']